Drafting apparatus

ABSTRACT

Drafting apparatus and method to draft sliver which has at least some of the staple fibers therein longer than the distance between center lines of adjacent pairs of rolls in a drafting system.

1451 Apr. 30, 1974 United States Patent 1191 Sanders 3,409,946 11/1968 Whitehurst...... 3,429010 2/1969 DRAFIING APPARATUS [75] Inventor:

Grady H. Sanders, Spartanburg, FOREIGN PATENTS OR APPLICATIONS Assignee: Deering Milliken Research Corporation, Spartanburg, SC.

Aug. 17, 1972 [21] Appl. No.: 281,563

[22] Filed:

Primary ExaminerDorsey Newton Attorney, Agent, or Firm-Norman C. Armitage; H. William Petry; Earle R. Marden ABSTRACT Drafting apparatus an d niethod to draft sliver which 6 5 mem W52 l v 146 umzs n 92 2 mmn wmm "0H mmm n n. 704 "ni mmmmo nnnoo HUUZ W2 mm. mmr. mum

mfw UI-F HUN 555 has at least some of the staple fibers therein longer than the distance between center lines of adjacent References Cited UNITED STATES PATENTS pairs of roll s in a drafting system.

3,001,241 Aymerich 191244 6 Claims, 3 Drawing Figures DRAFTING APPARATUS This application is a division of Application Ser. No. 179,022, filed Sept. 9, 1971.

In recent years the textile industry has gone into production of yarn which contains longer and longer staple fibers. This yarn is either a blend of long and short staple fibers or composed of all long staple fibers. It is very difficult to draft long fibers on spinning frames on the cotton system since the ratch or distance between pairs of drafting rolls is too short to draft long staple fibers of 3 inches or more length. Various techniques have been tried on these spinning frames but involved expensive modifications of the frame and resulted in poor quality yarn.

Therefore it is an object of the invention to provide a method and apparatus to draft long staple fibers which does not involve expensive modification to the spinning frame and provides a high quality yarn.

Other objects and advantages of the invention will become clearly apparent as the specification proceeds to describe the invention with reference to the accompanying drawings, in which:

FIG. 1 is a top view of the new and improved drafting arrangement;

FIG. 2 is a cross-sectional view of the drafting arrangement shown in FIG. 1; and

FIG. 3 is a view showing the cradle side plate mounting in relation to the front and middle drafting rolls.

Looking now to the drawings, the drafting arrangement comprises three sets of drafting rolls, namely, back rolls and 12, middle rolls l4 and 16 and front rolls l8 and 20. Each set of rolls has the rolls in nip forming engagement with each set of rolls being driven by any suitable means, such as motors 21, 23, and 25, schematically represented in FIG. 1, at a faster rate than the preceding set of rollsto provide the desired degree of drafting of the fibers in the zones between the respective pairs of rolls.

As pointed out previously, the purpose of this invention is to provide a method and apparatus to draft long staple fibers on a conventional cotton spinning frame on which the normal ratch' is about 4 inches from the center line of the rear rolls to the center line of the front rolls. T o accomplish this a new and novel drafting cradle is provided. The drafting cradle has a pair of side walls 22 and 24 each having a notch 26 to engage the lower front roll and another surface 28 to engage the lower middle roll 16. Interconnected between the side walls 22 and 24 is an apron guiding member 30 which has a concave surface 32 engaging the surface of the roll 16 and two apron reversing portions 34 and 38. The apron reversing portions are connected by an apron guiding surface to guide the apron 42 from apron reversing portion 34 to apron reversing portion 38. Another apron guiding surface 44 extends between the apron reversing portion 38 and the concave surface 32. Preferably the apron guiding member 30 will be made in two sections with one section molded to side 22 and the other section 24 so that they will mate together.

Side walls 22 and 24 have notches 46 therein to accommodate the stub shafts 48 and 50 connected to the apron reversing nose portion 52 of the elongated apron guide member 54 which extends across the width of apron 53. Attached to the stub shafts 48 and 50 are tabs 56 and 58 to aid in maintaining the cradle walls 22 and 24 in a predetermined spaced relationship. Each of the side walls has an oval shaped notch 60 therein to accommodate a dowel 62 attached to the side of the apron guide member 54. A screw member 64 is screwed down through the top of each side wall 22 and 24 and through each dowel 62 to adjust the tension in the apron 53 and the tensor opening between the aprons 42 and 53 at the respective nose portions 38 and 52. It can be seen that if the screw 64 is screwed in the downward direction the nose portion 52 will move upwardly in the notches 46 and vice versa, thereby providing ease of adjustment of the tensor opening without replacement of parts.

In the upper portion of the cradle walls 22 and 24 are further notches 65 to accommodate the stub shafts 66 and 68 attached to bar member 70. Tabs 72 and 74, like tabs 56 and 58, also aid in maintaining the spaced relationship of the side walls 22 and 24. Another notch 76 is located in each of the bottom portions of the cradle side walls 22 and 24 to accommodate the bar member 78 for further support of the spaced relationship of the cradle walls.

The cradle walls 22 and 24 are each molded with a hook portion 80 to define a cavity into which the upper roll is guided into nip forming relationship with roll- 16 by the weight arm (not shown) of the drafting system.

In operation a sliver or roving of fibers F is supplied into the nip of rear rolls 10, 12 through a conventional condenser 81. From the nip of rolls 10, 12 the fibers F wrap partially around roll 10 and are directed upwardly over bar 70. From the bar the fibers F pass downwardly into the nip of the middle rolls 14, 16. At the nip of rolls l4, 16 the drafting aprons contact the fibers F and aid in guiding the fibers around the roll 14 backwardly to and around the reversing portion 34 of the apron guiding member 54 and down the apron guiding surface 40 into the nip of front rolls 18, 20. From the nip of rolls 18, 20 the fibers are twisted into yarn Y by the conventional ring R and traveler T and taken up on bobbin B.

It should be noted that the fiber path between the nip of rolls l0, l2 and rolls 14, 16 as well as the fiber path between rolls 14, 16 and 18, 20 is considerably longer than the normal fiber path which normally would be directly from one nip to the next adjacent nip. Therefore, much longer fibers can be drafted without the individual fibers being caught between two adjacent hips and being broken due to thedifferential speed of the rolls.

Although I have described in detail the preferred em bodiment of my invention I contemplate that many changes may be made without departing from the scope of spirit of my invention and I desire to be limited only by the claims. a

I claim:

1. A drafting system comprising: a first set of rolls in nip forming relationship, a second set of rolls in nip forming relationship spaced from said first set of rolls, a third set of rolls in nip forming relationship spaced from said second set of rolls, means to drive one roll of each set of rolls all in the same direction and means operably associated with said second set of rolls to guide fibers from said second set of rolls in a direction away from said third set of rolls and then reverse the direction of fibers to supply fibers into the nip of said third pair of rolls, said means operably associated with said second set of rolls including drafting aprons around each roll in said second set of rolls and apron guiding membersin each of said aprons, said apron guiding members being in contiguous relationship with each other, said apron guiding members being supported by spaced wall members mounted on at least one of said rolls of said second set of rolls, one of said wall members having a slot therein, means to vary the contiguous relationship between said apron guiding members including a dowel connected to one of said apron guiding members and projecting through said slot and screw means in said wall member in which said slot is located engaging said dowel.

2. A drafting system comprising: a first set of rolls in nip forming relationship, a second set of rolls in nip forming relationship spaced from said first set of rolls, a third set of rolls in nip forming relationship spaced from said second set of rolls, drafting aprons around each roll of said second set of rolls, an apron guiding member mounted inside of each of said aprons, one of said apron guiding members having a concave surface abutting the roll of said second set of rolls about which its respective apron is located, each of said apron guiding members having at least two apron reversing portions to increase the path of flow of fibers introduced into said drafting system and means supplying fiber to be drafted into the nip of said first set of rolls.

3. The drafting system of claim 2 wherein said apron guiding members are supported by a pair of spaced wall members operably associated with said second set of rolls of said drafting system.

set ofrolls. 

1. A drafting system comprising: a first set of rolls in nip forming relationship, a second set of rolls in nip forming relationship spaced from said first set of rolls, a third set of rolls in nip forming relationship spaced from said second set of rolls, means to drive one roll of each set of rolls all in the same direction and means operably associated with said second set of rolls to guide fibers from said second set of rolls in a direction away from said third set of rolls and then reverse the direction of fibers to supply fibers into the nip of said third pair of rolls, said means operably associated with said second set of rolls including drafting aprons around each roll in said second set of rolls and apron guiding members in each of said aprons, said apron guiding members being in contiguous relationship with each other, said apron guiding members being supported by spaced wall members mounted on at least one of said rolls of said second set of rolls, one of said wall members having a slot therein, means to vary the contiguous relationship between said apron guiding members inclUding a dowel connected to one of said apron guiding members and projecting through said slot and screw means in said wall member in which said slot is located engaging said dowel.
 2. A drafting system comprising: a first set of rolls in nip forming relationship, a second set of rolls in nip forming relationship spaced from said first set of rolls, a third set of rolls in nip forming relationship spaced from said second set of rolls, drafting aprons around each roll of said second set of rolls, an apron guiding member mounted inside of each of said aprons, one of said apron guiding members having a concave surface abutting the roll of said second set of rolls about which its respective apron is located, each of said apron guiding members having at least two apron reversing portions to increase the path of flow of fibers introduced into said drafting system and means supplying fiber to be drafted into the nip of said first set of rolls.
 3. The drafting system of claim 2 wherein said apron guiding members are supported by a pair of spaced wall members operably associated with said second set of rolls of said drafting system.
 4. The drafting system of claim 3 wherein a means to vary the spatial relationship of said aprons is operably associated therewith.
 5. The drafting system of claim 4 wherein said means to vary the spatial relationship is a dowel connected to one of said apron guiding members which projects through a slot in one of said wall members and a screw means screwed into said dowel.
 6. The drafting system of claim 5 wherein said dowel member is connected to the apron guiding member guiding the apron around the upper roll of said second set of rolls. 